Intestines from lamb, sheep, hog and beef are used throughout the world for stuffing with chopped-up meat and other ingreditents for consumption as sausage. Commercially, these intestines when cut to desired length are known as casings. After the intestines are removed from the animal and cleaned, the intestinal tissue is checked for quality and calibrated for diametral size, i.e., 22/24, 24/26, 35/37, 39, 42 millimeters, to accommodate the specifications of individual sausage manufacturers. Calibration for diameter and quality occurs in a known manner by inflating the intestine or casing with pressurized water or air measurable parts of sheep intestine average about 28-30 yards, hog approximately 17 yards with end to end diametral changes varying as much as 30-40%) and checking the diameter with a standard measuring gauge. In this manner, intestinal lengths may be calibrated as, for example, a 34/36 millimeter selection, and thereafter cut into predetermined casing lengths. Unusable parts of intestine may also be removed by cutting.
In the manufacture of sausage casings, it is important that the casings be cut squarely since when the wet casing (which is slippery and made of a very strong connective tissue known as Collagen) is inserted on a stuffing horn, this must be rapidly accomplished by an operator who by the flick of his fingertips must locate the opening or mouth of the casing and slip it onto the stuffing horn enabling the rest of the casing to be pulled onto the horn. If the casing is not cut squarely, the operator will find it difficult to locate the casing mouth, losing precious seconds, which is in turn reflected down the production assembly line. This loss of production time is crucial considering that an operator will normally work with approximately several hundred to several thousand casings daily. As the term is used in the present specification, a "square cut" means that the entire annular end portion of the wet casing is located in a plate extending sutstantially perpendicular to the longitudinal axis of the casing.
Known cutting knives presently used for cutting sausage casings are generally unsatisfactory for several reasons. One problem, for example, is that these cutting knives generally utilize either a regular, single or double shearing blade that is susceptible to breaking and that is often counted in an unsafe, exposed manner, causing injury the operator's hands. Such knives also tend to be subject to corrosion and are often difficult to clean. The cutting edge of these prior art knives wear quickly and are difficult to replace in a rapid manner.
One knife construction of which I am aware comprises a straight knife blade exposed within a groove of a metal post. This mounting arrangement results in a ruptured or jagged cut, instead of the desired square cut, and the groove is subject to clogging. This type of knife is also difficult to re-sharpen or clean and, after several sharpenings, the space between the knife edge and groove increases, rendering the knife useless.